Does not really apply because unlike plastic surgery, you have the ability to edit with no limits on time or revision count. Plus the is no requirement that ties you to the original. My first book as a human male as the lead, I could revise it once and make him a female. Then revise it again and make her a hermaphrodite. Or a dinosaur, or eliminate the character completely. Since there is no restriction on what you can do with a story, there is no limit to the number of revisions and one more revision always has the chance to make it better.